These words are often used interchangeably as their meanings are very similar.
CONCENTRATE
1. think intensely/ direct your thoughts or attention
- We need to concentrate on the task. (We need to direct our attention towards the task and stop doing other things.)
- I can’t concentrate if you keep telling me how to do it. (I can’t think intensely about something, because you’re distracting me.)
- I’ve decided to concentrate on finding a better job. (I will give all my attention to this task.)
2. bring things together in one (small) place
- Wealth is concentrated in the hands of a few.
- The riots were concentrated in the industrial part of the town.
FOCUS
1. give (special) attention to something
- She should focus on her studies. (She should give more attention to her studies.)
- The exercises focus on different groups of vocabulary. (The exercises give special attention to different groups of vocabulary.)
- Try to focus on what truly matters. (Don’t worry about other things, give special attention to what truly matters.)
2. narrow your focal point so that you see something better
- The camera focused on the actor’s face.
- It was hard for his eyes to focus in the dark.
Recommended for you:
List of Sentence Connectors in English with Examples!
Questions and Answers to Prepare You for a Job Interview
Difference between Connect, Contact, Conduct and Communicate